Intraperitoneal fat is associated with thickening of the thoracic aorta in individuals at high risk for cardiovascular events

Sperm Dysfunction in the Testes and Epididymides due to Overweight and Obesity Is Not Caused by Oxidative Stress

Obesity is a condition that has been linked to male infertility. The current hypothesis regarding the cause of infertility is that sperm are highly sensitive to reactive oxygen species (ROS) during spermatogenesis in the testes and transit through the epididymides, so the increase in ROS brought on by obesity could cause oxidative stress. The aim of this study was to evaluate whether the activity of the enzymes catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPX) is capable of counteracting oxidative stress in sperm. The male Wistar rat was used as an overweight and obesity model, and analysis of fertility in these groups was carried out including the control group. Serum testosterone levels were determined, and the scrotal fat, testes, and epididymides were extracted. The epididymides were separated ini0 3 principal parts (caput, corpus, and cauda) before evaluating sperm viability, sperm morphology, damage to desoxyribonucleic acid of the sperm, and ROS production. The protein content and specific activity of the three enzymes mentioned above were evaluated. Results showed a gain in body weight and scrotal fat in the overweight and obese groups with decreased parameters for serum testosterone levels and sperm viability and morphology. Fertility was not greatly affected and no DNA integrity damage was found, although ROS in the epididymal sperm increased markedly and Raman spectroscopy showed a disulfide bridge collapse associated with DNA. The specific activities of CAT and GPX increased in the overweight and obesity groups, but those of SOD did not change. The amounts of proteins in the testes and epididymides decreased. These findings confirm that overweight and obesity decrease concentrations of free testosterone and seem to decrease protein content, causing poor sperm quality. Implications. An increase in scrotal fat in these conditions fosters an increase of ROS, but the increase of GPX and CAT activity seems to avoid oxidative stress increase in the sperm without damaging your DNA.

Effects of Exercise and Weight Loss on Proximal Aortic Stiffness in Older Adults With Obesity

BACKGROUND

Obesity may accelerate age-related increases in aortic stiffness. Although aerobic exercise training generally has favorable effects on aortic structure and function, exercise alone may not be sufficient to improve aortic stiffness in older adults with obesity. We determined the effects of aerobic exercise training with and without moderate- to high-caloric restriction (CR) on the structure and function of the proximal aorta in 160 older (65-79 years) men and women with obesity (body mass index=30-45 kg/m²).

METHODS

Participants were randomly assigned to 1 of 3 groups: aerobic exercise training only (treadmill 4 days/week for 30 minutes at 65% to 70% of heart rate reserve; n=56), aerobic exercise training plus moderate CR (n=55), or aerobic exercise training plus more intensive CR (n=49) for 20 weeks. Aortic pulse wave velocity, aortic distensibility, and other measures of aortic structure and function were assessed by cardiovascular magnetic resonance imaging. Pearson correlation coefficients were examined to assess associations between changes in proximal aortic stiffness and changes in fitness, fatness, and other potential confounders.

RESULTS

Weight loss in the aerobic exercise training plus moderate CR (-8.0 kg [95% CI, -9.17 to -6.87]) and aerobic exercise training plus more intensive CR (-8.98 kg [95% CI, -10.23 to -7.73) groups was significantly greater compared with the aerobic exercise training-only group (-1.66 kg [95% CI, -2.94 to -0.38]; P<0.017 for both). There were significant treatment effects for descending aorta distensibility (P=0.008) and strain (P=0.004) and aortic arch pulse wave velocity (P=0.01) with the aerobic exercise training plus moderate CR group having a 21% increase in distensibility (P=0.016) and an 8% decrease in pulse wave velocity (P=0.058). None of the aortic stiffness measures changed significantly in the aerobic exercise training-only or aerobic exercise training plus more intensive CR groups, and there were no significant changes in any other measure of aortic structure or function in these groups. Overall, increases in aortic distensibility were correlated with improvements in body weight and body fat distribution, but these associations were not statistically significant after adjustment for multiple comparisons.

CONCLUSIONS

In older adults with obesity, combining aerobic exercise with moderate CR leads to greater improvements in proximal aortic stiffness than exercise alone. Registration: URL: https://clinicaltrials.gov; Unique identifier: NCT01048736.

The relationship between abdominal fat and change in left ventricular ejection fraction in cancer patients

Objectives

Prior studies have identified a relationship between body mass index (BMI) and intraperitoneal (IP) fat with heart failure; however, in prior studies of cancer patients receiving potentially cardiotoxic chemotherapy, elevations in BMI have not necessarily been associated with decrements in heart function. This study tested the hypothesis that IP fat may be associated with left ventricular ejection fraction (LVEF) decline among cancer patients receiving potentially cardiotoxic chemotherapy.

Methods

In this prospective study of 61 cancer patients (23 breast cancer, 32 lymphoma, and 6 sarcoma), IP fat and other assessments of body composition, and changes in LVEF from pre- to postcancer treatment using noninvasive magnetic resonance imaging was ascertained.

Results

After accounting for age, baseline LVEF, and confounding variables, pre- to 24-month post-treatment LVEF changes were inversely correlated with IP fat (r = -0.33; p = 0.02) and positively correlated with measures of subcutaneous (SQ) fat (r = 0.33; p = 0.01). These LVEF changes were not correlated with BMI (r = 0.12; p = 0.37).

Conclusion

Among patients receiving potentially cardiotoxic chemotherapy, pretreatment IP fat was associated with subsequent declines in LVEF. There was no association between BMI and LVEF decline. These findings may be related to a potential protective effect of SQ fat.

Racial differences in circulating levels of the soluble receptor for advanced glycation endproducts in middle-aged and older adults

BACKGROUND

Low levels of the soluble receptor for advanced glycation endproducts (sRAGE) have been implicated in a number of chronic diseases. Previous studies indicate that sRAGE levels are ~30% lower in Blacks compared to Whites. However, the reasons for these differences are unclear.

PURPOSE

We aimed to identify predictors of circulating sRAGE biomarkers among Black and White adults at high cardiac risk.

METHODS

Serum levels of total sRAGE, endogenous secretory RAGE (esRAGE), carboxymethyl-lysine (CML, a major RAGE ligand), and their ratios were measured in 99 Blacks and 454 Whites.

RESULTS

Blacks had a more adverse cardiovascular risk profile, as well as lower median levels of total sRAGE (972 vs. 1564pg/ml) and esRAGE (474 vs. 710pg/ml) compared to Whites (p<0.0001). In addition, the proportion of esRAGE was higher in Blacks (47% vs. 44%, p=0.02), as were the CML/total sRAGE (0.89 vs. 0.56ng/pg) and CML/esRAGE (1.72 vs. 1.20ng/pg) ratios (p<0.0001). Racial differences persisted after adjustment for key covariates including age, gender, tobacco use, comorbidities, BMI, blood pressure, glucose, insulin, triglycerides, C-reactive protein, and renal function (p<0.05). Race alone accounted for nearly half of the variability in total sRAGE levels (10.6%; model explained 23.9%). In stratified analyses, gender and heart rate were independently associated with total sRAGE and esRAGE in Whites, while CML and C-reactive protein were associated with total sRAGE in Blacks.

CONCLUSIONS

We identified several independent predictors of sRAGE biomarkers. Notably, Black race was associated with an adverse AGE/RAGE profile, including lower sRAGE and higher CML/sRAGE ratios.

Adiposity Is Associated with Gender-Specific Reductions in Left Ventricular Myocardial Perfusion during Dobutamine Stress

Background

Obesity and visceral adiposity are increasingly recognized risk factors for cardiovascular disease. Visceral fat may reduce myocardial perfusion by impairing vascular endothelial function. Women experience more anginal symptoms compared to men despite less severe coronary artery stenosis, as assessed by angiography. Women and men have different fat storage patterns which may account for the observed differences in cardiovascular disease. Therefore, our objective was to evaluate the relationship between visceral adipose tissue distributions and myocardial perfusion in men and women.

Methods

Visceral and subcutaneous fat distributions and myocardial perfusion were measured in 69 men and women without coronary artery disease using magnetic resonance imaging techniques. Myocardial perfusion index was quantified after first-pass perfusion with gadolinium contrast at peak dose dobutamine stress.

Results

We observed inverse relationships between female gender (r = -0.35, p = 0.003), pericardial fat (r = -0.36, p = 0.03), intraperitoneal fat (r = -0.37, p = 0.001), and retroperitoneal fat (r = -0.36, p = 0.002) and myocardial perfusion index. Visceral fat depots were not associated with reduced myocardial perfusion at peak dose dobutamine in men. However, in women, BMI (r = -0.33, p = 0.04), pericardial fat (r = -0.53, p = 0.02), subcutaneous fat (r = -0.39, p = 0.01) and intraperitoneal fat (r = -0.30, p = 0.05) were associated with reduced myocardial perfusion during dobutamine stress.

Conclusions

Higher visceral fat volumes are associated with reduced left ventricular myocardial perfusion at peak dose dobutamine stress in women but not in men. These findings suggest that visceral fat may contribute to abnormal microcirculatory coronary artery perfusion syndromes, explaining why some women exhibit more anginal symptoms despite typically lower grade epicardial coronary artery stenoses than men.

Abnormal stress-related measures of arterial stiffness in middle-aged and elderly men and women with impaired fasting glucose at risk for a first episode of symptomatic heart failure

Background

Abnormal resting arterial stiffness is present in middle‐aged and elderly persons with abnormalities of fasting glucose (diabetes or impaired fasting glucose) and is associated with exercise intolerance. We sought to determine whether these same persons exhibited stress‐related abnormalities of arterial stiffness.

Methods and Results

We analyzed dobutamine magnetic resonance stress imaging results from 373 consecutively recruited persons aged 55 to 85 years with normal fasting glucose, impaired fasting glucose, or diabetes who were at risk for but without symptomatic heart failure. Personnel blinded to participant identifiers measured arterial stiffness (brachial pulse pressure/left ventricular stroke volume indexed to body surface area, the aortic elastance index [brachial end‐systolic pressure/left ventricular stroke volume indexed to body surface area], and thoracic aortic distensibility) at 80% of the maximum predicted heart rate response for age. Participants averaged 69±8 years of age; 79% were white, 92% were hypertensive, and 66% were women. After accounting for hypertension, sex, coronary artery disease, smoking, medications, hypercholesterolemia, and visceral fat, we observed an effect of glycemic status for stress measures of arterial stiffness in those with diabetes and impaired fasting glucose relative to those with normal fasting glucose (P=0.002, P=0.02, and P=0.003, respectively).

Conclusion

Middle‐ and older‐aged individuals with diabetes or impaired fasting glucose have higher stress measures of arterial stiffness than those with normal fasting glucose. These data emphasize the need for future studies with larger sample sizes to determine whether stress‐related elevations in arterial stiffness are related to exercise intolerance and future episodes of heart failure experienced by those with abnormalities of fasting glucose.

Clinical Trial Registration

URL: http://clinicaltrials.gov/. Unique identifier: NCT00542503.

Periaortic fat and cardiovascular risk: a comparison of high-risk older adults and age-matched healthy controls

Objective

Fat accumulation around the heart and aorta may impact cardiovascular (CV) health. The purpose of this study was to conduct a systematic investigation to examine potential associations of these fat depots with risk factors for CV events, which has not been done before.

Methods

Pericardial fat, periaortic fat around the ascending aorta (AA), descending aorta (DA) and aortic arch, and abdominal subcutaneous and visceral fat were measured by MRI in older adults with (n=385, 69±8 years, 52% female) and without (n=50, 69±8 years, 58% female) risk factors for a CV event.

Results

Individuals with CV risk factors exhibited greater fat volumes across all fat depots compared to those without risk factors. In analysis of covariance accounting for age, gender, race/ethnicity, diabetes, hypertension, coronary artery disease, smoking, and BMI, individuals with risk factors possessed higher epicardial, pericardial, AA, DA, and abdominal visceral fat (p<0.05). When matched one-to-one on age, gender, race/ethnicity, and BMI, AA and DA fat were higher in those with versus without CV risk factors (p<0.01).

Conclusions

Older adults with a high risk for CV events have greater periaortic fat than low-risk adults, even after accounting for BMI. More studies are needed to determine whether greater periaortic fat predicts future CV events.

Serum fibroblast growth factor 21 is predictive of combined cardiovascular morbidity and mortality in patients with type 2 diabetes at a relatively short-term follow-up

AIMS

We hypothesised that serum fibroblast growth factor 21 (FGF-21), a novel adipokine with postulated insulin-sensitizing effects, may be predictive of cardiovascular (CV) events in patients with type 2 diabetes (DM2) at a relatively short-term follow-up.

METHODS

Serum FGF-21 levels were assessed in 87 DM2 patients, aged 57-66 years, with the median duration of diabetes of 10 years, who were referred to the Department of Endocrinology for routine annual metabolic assessment. During a follow-up of 24 months, overall mortality, CV mortality and CV nonfatal events were registered. Cox proportional hazards regression assessed adjusted differences in CV morbidity and mortality risk.

RESULTS

Patients stratified according to serum FGF-21 levels ≤ and > the median value of 240.7 pg/mL showed no significant differences at baseline in gender distribution, diabetes duration, insulin therapy, BMI, biochemical profiles and previous CV events. At 24-month follow-up, 21 (24.1%) patients experienced a nonfatal CV event. A significantly (P=0.0013) higher incidence of the combined end point of CV morbidity and mortality was observed in the FGF-21>240.7 pg/mL group. In the multivariate Cox proportional hazards regression model, the presence of FGF-21>the median value was associated with a significant increase in the risk of the combined end point of CV morbidity and mortality (HR: 4.7, 95% CI 1.67-13.24).

CONCLUSIONS

The obtained results support the prognostic value of FGF-21 in DM2 and may provide a useful tool for stratification of CV prognosis in DM2 patients.